Furnace.



E. T. DAVISON.

FURNACE. Y APPLICATION FILED JAN. 8, 1912.

Patented May 21, 1912.

' 2 SHEETS-SHEET 1.

-uLUMBEA unmask/um c0., WASHINGTON, n. c.

E. T. DAVISON.

FURNACE. APPLICATION FILED JAN. 8, 1912.

Patented May 21, 1912.

2 BHEETS SHBET 2.

a F/Wl'l? 77 P4 visa/7' mtazucw f E COLUMBIA PLANOGRAPH CO.- WASHINUTON.D. C.

UNITED STATES PATENT OFFICE.

ELWIN THEODORE DAVISON,

or- ATHENIA, NEW JERSEY.

FURNACE.

useful Improvements in Furnaces, of which 'the following is aspecification.

Heretofore various constructions of fur naces have been devised forincreasing the fluidheating capacity, as for-example, in the Patent No.448,391 of March 17, 1891, it has been proposed to superimpose in thefire-pot a plurality of sectionsor fluid heating chambers having,corrugated bottoms, in such a manner that the products of combustion arecompelled to pass through the peripheral openings in one section, and acentral opening in the next succeeding section alternately,.therebyresulting in the tortuous passage of the same along to thestack; While the provision of corrugations in the surface of these fluidheating chambers theoretically increases the heating surface area ofsaid chambers some 50 to 90% over and above that ofa plane surface,nevertheless, the interposition of such a large number of barriers inthe path of the upwardly flowing gaseous products tends to retard thedraft tosuch an extent that for many purposes such a construction cannotbe satisfactorily employed- This is particularly true when it isdesiredto burn soft coal or like grades of fuel; Moreover, the said surfaces,because of the retardation of the draft of the furnace, causes thedeposition of the soot which results in effectively insulating the saidsurfaces against the conduction. of heat therethrough with the resultthat the actual efficiency of the furnace, particularly as stated whenemploying a low grade of fuel, is not very largely increased either bythe provision of these corrugated surfaces or by the great extent of theheating surfaces over which the products of combustion are causedt'opass. f

The object of this invention is the provision of such a construction offurnace as will afford a maximum of heating surface within the fire-potwithout resulting in the excessive retardation of'the draft, or theinterposition of obstructions which will efiect creased. over that of a:plane'surface, correthe, deposition of large quantities of V sootthereon. surface of the fluid chamber inthe construction hereinafterdescribed, is enormously in- Specification of Letters Patent.

In fact,v the area of the heating PatentedMay 21',,1 912:

Application filed January 8, 1912. Serial No. 669,969.

.sponding in extent toithe horizontal crosssectional area of the fluidcompartments and air chambers, the construction is such; that 'the'draftis not seriously impaired and there is no material deposition. of sootuponthe heating surface exposed to theproducts of combustion. Moreover,what soot,if: any, is

deposited can. be readily, removed, because of the novel arrangement of:the chambers,-.

Wlllcll are employed; in this construction.

The invention is fully set forth inthe fol lowing detailed descriptionand drawings forming a part thereof, inwhich Figure 1 is a frontelevation, chiefly in ,3 section, of a furnace of the hot-water type Fg. 2 is a vertical. cross s'ectionf thereof;- Flg. 3 is a cross-sectionalong" the line 3-3 of Fig. 2, and Fig; 4 is a cross-section along;

the line 4-4 of Fig.v 2.

Referring to the drawings and the cons 'struction shown therein,- thereference, nu+ meral 1 designates the-shell, and within this is arrangeda fire-pot 2 of the well known construction, the lower portion of thesame being preferably of truncatedv cone-like configuration, and theupper portion being preferably cylindrical; A fluid-chamber 2 Eembracesthe said fire-pot, thesamebeing in this instance adapted to receive hotwater ialthough obviously, it. is suited for the reiception of air orother fluid as may be de-- fsired. Suitable grate-bars 3- are provided,-tarranged in the usual manner at tllG-bOfitOIIl; iof said fire-pot abovethe ash-pit 4,, and as ishown; access may be had both to said fire- ;potand said ash-pit by the usual swinging. jdOOl'S. The upper end of saidfire-pot as shown, is formed into a series of waterand jair compartments5 and 5% respectively, said water compartments being preferably f aboutone-half the width of said air compar t iments. In practice I preferabout the pro portion ofone-halfinch forthe water com.- partments andone inch for the air compartments in the furnace, with, a firerpot of 24;30 inches square and, 4'8 inches high, although these proportions mayhe obvio sly. somewhat varied as hereinafter set forth. Preferablytwocompartments of greater depth than the aforesaid compartments 5,- asindicated by the reference numeral (i are provided, and thereby theupper-end of, said fire-pot-is divided into approximately three channelsin the manner showm, The smokepipe 7, which extends parallel with theaxis of said compartments 5 and 6, opens through I which is intermediatethe rear end of said compartments and the wall of the fire-pot.

The usual stack 8 of any suitable type, may be provided with a damper 9,connected with said smoke-pipe or outlet pipe.

A fluid heating chamber 1) projects downwardly from a point midwaybetween the top and bottom of the cylindrical portion of said fire-pot.This chamber, which extends almost but not entirely, across thefire-pot, is also provided with fluid compartments 10 which are spacedfrom each other so as to form air-spaces or culsde-sac 10. In order toinsure the efficient heating of the fluid in these compartments, each ofsaid air spaces is preferably constructed about twice the width of thecorresponding fluid compartment, and thereby the gaseous products ofcombustion are admitted in rel atively large quantities to saidculs-de-sac. However, owing to the size of the same and the smoothexterior surfaces possessed there by there is comparatively littleretardation of the flow of the said gaseous products along the entireextent of the surface of these culs-de-sac. The said fluid chamber issupported by means of a water-neck or fluid conduit 11, which isintegrally cast with the chambered top of said fire-pot and projectsdownwardly therefrom to a depth corresponding to that of thecompartments 6.

"" In order to prevent the direct passage of the gaseous combustionproducts to the smoke-pipe, the said fluid chamber 6 is preferablysecured directly to the same wall 0 of the fire-pot as that whichreceives said smoke-pipe. On the other hand a passage 0 is providedintermediate the end of said fluidchamber b and the opposite wall of thefire-pot of sufficient size to permit of the free flow of the saidgaseous products from the fire-pot after the same have traveled over theexterior surfaces of said fluid compartments 10. The said passage 0opens into the channels d, cl, d, which in turn empty into the exitchamber a, from which direct communication is afiorded with saidsmoke-pipe.

The reference numeral 16 designates an outflow pipe for conducting theheated water to the radiators in the building, which are connected inthe usual manner with the return flow pipes 14' and 15. The bottom ofthe jacketed portion of the shell being approximately at the lower endof the firepot 2, the return pipes 12, 13 are tapped through the shell 1at this point, as shown in Fig. 1. Thus a portion of the return waterpasses into the interior of the shell 1 and other portions into theheating chamber b, which as described, is connected by the pipe 11 withthe interior of the shell 1 near the top thereof.

When employing a fire-pot of rectangular configuration, and havingdimensions 24: by 30, and a heating chamber spaced four inches from thefront wall of the fire-pot which firepot is 48 in depth, the wholeheating surface area of said fire-pot will be 3672 square inches, whenthe heating chamber is omitted. When however, as shown herein, a heatingchamber is employed, and as stated spaced 4 from the front wall of thefire-pot, and having fluid-compartments four inches deep and one-halfinch in width with intervening culs-de-sac of one inch width, theheating surface area of these projecting compartments is equal to 3744square inches, or approximately six times that of a plane surfacecorresponding in area to the cross-sectional area of said fluidcompartments and said air chambers combined. As shown, the dependingcom-partments of said fluid-heating chamber are arranged to impede thefree escape of the gaseous products of combustion from the fire-pot, andthe same must therefore be arranged to intersect the vertical planeincluding the axis of the outlet conduit from said fire-pot and thecenter point of said fire-pot. The fluid compartments depending from thetop of said fire-pot should on the other hand afford as littleresistance as possible to the passage of the gaseous products ofcombustion to the outlet opening in said fire-pot, and accordingly theseare arranged in parallelism to the vertical plane including the axis ofthe outlet conduit from said firepot and the center point of saidfire-pot.

For air heaters, the heating chamber 12 is connected directly with theinterior of the shell A, which is provided at the bottom with the usualfresh air inlet duct, and at the top with hot air fines for conductingthe heated air to the various rooms to be heated; otherwise theconstruction is practically the same as above described with referenceto the hot water heater shown.

Owing to the vertical arrangement of the fluid compartments, it becomesextremely easy to tap off or break off any soot or other deposittherefrom, and it is evident that access may be had to the compartmentsdepending from. the interior fluid heating chamber through the door ofthe fire-pot and through the chute 17 and door 18. Suitable implementscan be introduced to clean off the fluid compartments depending from thetop of the fire-pot.

Having thus described my invention,

what I claim and desire to secure by Letters Patent is:

1. A furnace, comprising a fire-pot and a shell, an exterior fluidheating chamber intermediate the same, an interior fluid heat ingchamber positioned in the upper portion of said fire-pot and providedwith depending fluid compartments, each compartment being separated froman adjacent compartment by an air chamber closed at the top and openedat the bottom and said compartments bein of sufficient depth .toincrease the heatmg-surface area exposed to the products of combustionat least 150% in excess of the total horizontal cross-sectional area ofsaid compartments and said airchambers separating the same, and meansfor preventing the unimpeded escape of the products of combustion fromsaid fire-pot prior to the passage of the same over the said chamberedinferior surface of said heating chamber and for permit-ting of thesubstantially unimpeded escape of said products of combustion afterpassage over said surface.

2. A furnace, comp-rising a fire-pot and a shell, an exterior fluidheating chamber intermediate the same, an interior fluid heating chamberpositioned in the upper portion of said fire-pot and provided withdepending fluid compartments arranged to intersect the vertical planeincluding the axis of the outlet conduit from said fire-pot and thecenter point of said fire-pot, each compartment being separated from anadjacent compartment by an air chamber closed at the top and opened atthe bottom and said compartments being of sufiicient depth to increasethe heating-surface area exposed. to the products of combustion at least150% in excess of the total horizontal cross-sectional areaof saidcompartments and said air chambers separating the same, and means forpreventing the unimpeded escape of the products of combustion from saidfire-pot prior to the passage of the same over said chambered inferiorsurface of said heating chamber and for permitting of the substantiallyunimpeded escape of said products of combustion after passage over saidsurface.

3. A furnace, comprising a fire-pot and a shell, an exterior fluidheating chamber intermediate the same, an interior fluid heating chamberpositioned in the upper portion of said fire-pot and provided withdepending fluid compartments arranged to intersect the vertical planeincluding the axis of the outlet conduit from said fire-pot and thecenter point of said fire-pot, each compartment being separated from anadjacent compartment by an air chamber closed at the top and opened atthe bottom and said compartments being of suflicient depth to increasethe heating-surface area exposed to the products of combustion at least150% in excess of the total horizontal cross-sectional area of saidcompartments and said air chambers separating chambers arranged abovesaid fluid heatingchamber and extending in parallelism with the planeincluding the axis of the outlet conduit from said fire-pot and thecenter point of said fire-pot, said compartments being of sufficientdepth to increase the heating-surface area exposed to the products ofcombustion at least 150% in excess of the total horizontalcross-sectional area of said compartments and said air chambersseparating the same, and means affording communication between saidexterior fluid heatin chamber and the fluid compartments posltionedwithin said firepot.

4:. A furnace, comprising a fire-pot and a shell, an exterior fluidheating chamber intermediate the same, an interior fluid heating chamberpositioned in the upper portion of said fire-pot and provided withdepending fluid compartments, each c0mpartment being separated from anadjacent compartment by an air chamber closed at the top and opened atthe bottom and said compartments being of suflicient depth to increasethe heating-surface area exposed to the products of combustion at least350% in excess of the total horizontal cross-sectional area of saidcompartments and said air-chambers separating the same, and means forpreventing the unimpeded escape of the products of combustion from saidfire-pot prior to the passage of the same over the said chamberedinferior surface .of said heating chamber and for permitting of thesubstantially unimpeded escape of said products of combustionafter'passage over said surface.

5. A furnace comprising a fire-pot and a shell, an outlet pipe from saidfire-pot, longitudinal hollow vertical compartments extending downwardlyfrom'the top of said fire-pot and forming in the upper portion of saidfire-pot a plurality of channels 1 5 adapted to receive a current ofgaseous products of combustion flowing to said outlet pipe andsub-dividing said current into a plurality of currents, a horizontalpartition adapted to substantiallyrcontact with,

the bottom of said longitudinal vertical compartments to prevent thedirect passage of the products of combustion to said outletpipe withoutpassage through said plurality of channels formed by said longi- 1Washington, I). G.

Copies of this patent may be obtained for five cents each, by addressingthe Commissioner of Patents,

